The present invention relates to an electronically controlled throttle apparatus which opens and closes a throttle valve of the motor vehicle by a motor controlled electrically.
As is described in Japanese Patent Application Laid-Open 1-315629 (1989), in the conventional electronically controlled throttle apparatus, a single throttle valve mounted on a single bore is controlled to be made open and close by a DC motor. The motor and the throttle valve are placed so that their operation shafts may be parallel to each other and, they are coupled by a reduction gear at one end of each of their shafts. The extension of the throttle body in the direction of the air flow, that is, the height of the throttle body is about twice as much as the diameter of the motor, and the overall height of the throttle body in the axial direction is relatively high and the dead space between the motor and the throttle body is larger. This is because the height of the throttle body is required to be reserved when the throttle valve is fully opened and positioned to be parallel to the direction of the air flow.